The present invention relates to a clip removing tool and method used to remove a clip used to attach an optical connector to a backplane.
Backplane connectors have hitherto been provided as optical connectors of a plug-in type.
FIG. 36 shows an example of a backplane connector. In FIG. 36, reference numeral 1 denotes a plug-in unit, reference numeral 2 denotes a printed board, and reference numeral 3 denotes a backplane. Reference numerals 4a and 4b denote MPO connector plugs (hereinafter referred to as xe2x80x9cMPO plugsxe2x80x9d), reference numeral 5 denotes a printed board housing (hereinafter referred to as a xe2x80x9cPH housingxe2x80x9d), and reference numeral 6 denotes a backplane housing (hereinafter referred to as a xe2x80x9cBH housingxe2x80x9d).
With this backplane connector, by inserting the printed board 2 to which the PH housing 5 is fixed into the plug-in unit 1, the PH housing 5 is fitted into the BH housing 6 attached to the backplane 3 arranged on a side portion of the plug-in unit 1. The PH housing 5 and the BH housing 6 fitted into each other constitute an optical connector adapter 7. The optical connector adapter 7 allows the connection of the MPO plugs 4a and 4b inserted into the optical connector adapter 7 from its opposite sides. The MPO plug 4a inserted into the optical connector adapter 7 from the PH housing 5 side is inserted into the PH housing 5 beforehand. It is then inserted into the optical connector adapter 7 at the same time when the printed board 2 is inserted into the plug-in unit 1. A plurality of printed boards 2 can be densely accommodated in parallel in the plug-in unit 1. Consequently, this backplane connector allows optical connector adapters 7 to be densely mounted.
The MPO plugs 4a and 4b are optical connectors comprising an optical connector ferrule 4c specified in Japanese Industrial Standard JIS C 5981 and supported in a plastic housing.
FIG. 37 is an exploded perspective view showing a structure in which the BH housing 6 is mounted on the backplane 3. As shown in FIG. 37, the BH housing 6 is mounted on the backplane 3 so as to sandwich the backplane 3 between the BH housing 6 and a rear surface housing 9 arranged opposite the BH housing 6 via the backplane 3. That is, pins 10 projecting from the BH housing 6 arranged at the printed board 2 side (the left of FIG. 37) of the backplane 3 are inserted into an attaching slot 11 so as to project from the opposite side of the backplane 3. The rear surface housing 9 is fixed to the projecting ends of the pins 10 using screws 12. Thus, the backplane 3 is sandwiched between the BH housing 6 and the rear surface housing 9. A slot is formed in a housing main body 8 of the BH housing 6 and in the rear housing 9 so that the optical connector plug 4b (MPO plug) is inserted into these slots via the attaching slot 11 in the backplane 3. However, these slots are omitted from FIG. 37.
The BH housing 6 is mounted on the backplane 3 so as to be movable a small distance. For example, in FIG. 37, extended portions 13 formed by extending four corners of the rectangular attaching slot 11 allow the screws 12, connecting the BH housing 6 and the rear surface housing 9 together, to move a small distance. This movable range of the screws 12 allows the BH housing 6 to move a small distance. The movement of the BH housing 6 absorbs dimensional tolerances to the BH housing 6 and PH housing 5 to contribute to smooth fitting operations.
However, with the backplane connector, the small size (about 1.2 mm in diameter) of the screws 12 results in the need of much time and labor to fix the rear surface housing 9 using a hand tool. Furthermore, it takes much time and labor to form the pins 10, threaded holes 16 (see FIG. 37), and attaching slot 11 corresponding to the screws 12.
Furthermore, the movement range of the backplane housing 6 depends on the sliding resistance of the housing main body 8 and rear surface housing 9 to the backplane 3, the magnitude of the clearance between the housing main body 8 or rear surface housing 9 and the backplane 3, or the like. A small variation in the size of the clearance significantly affects the movement range or degree of freedom of the backplane housing 6. Accordingly, it takes much time and labor to adjust the clearance. That is, if a useless gap is created between the housing main body 8 and the rear surface housing 9 because of the tolerances to the backplane 3, notably the tolerance to its thickness dimension, then the movement range of the backplane housing 6 is unnecessarily widened. This makes it difficult to fit the printed board housing 5. In contrast, if the backplane 3 has a thickness larger than a predetermined one, it may be difficult to move the backplane housing 6 or fix the backplane housing 6 using the screws 12.
Thus, with the backplane connector of the conventional configuration, it takes much time and labor to ensure the desired movement range of the backplane housing 6. On the other hand, when the entire backplane 3 is formed precisely in view of these problems, costs increase sharply.
To solve these problems, the inventor has developed a backplane connector comprising a clip from which elastic pawls project and which is arranged opposite a backplane housing via a backplane so that the elastic pawls allowed to penetrate an attaching slot formed in the backplane engages with the backplane. Accordingly, the backplane housing is mounted on the backplane so that the backplane is sandwiched between the backplane connector and the clip. With this backplane connector, the movement range of the backplane housing can be set on the basis of the movable range of the elastic pawls in the attaching slot formed in the backplane. Consequently, compared to the conventional structure using screws, the movement range of the backplane housing can be set easily. Furthermore, ensuring the accuracy of formation of the elastic pawls reduces the need for the accuracy of formation required for the backplane housing and the parts of the clip other than the elastic pawls. Therefore, costs can be reduced.
However, this backplane connector requires development of a technique of easily disengaging the elastic pawls of the clip from the backplane housing when replacement of the clip or the like is carried out for replacement of the backplane housing, a change in movement range, or the like. That is, the backplane connector must have a reduced size in order to improve mounting density. Accordingly, it is desirable to reduce the elastic pawls or locking portions of the backplane housing on which the corresponding elastic pawls are locked. However, a reduction in the size of the locking portions and elastic pawls may make it difficult to disengage the elastic pawls from the locking portions. Conversely, when the size of the elastic pawls is increased in order to facilitate the disengagement, it is difficult to increase the mounting density. Furthermore, for example, the backplane housing mounted on the backplane of the plug-in unit is located at the innermost position of the plug-in unit. Thus, it is very difficult to disengage the elastic pawls of the clip from the backplane housing.
The present invention is provided in view of these problems. It is an object of the present invention to provide a clip removing tool and method that allows a clip to be disengaged easily from a backplane housing.
A first aspect of the present invention is a clip removing tool used to disengage an optical connector from a clip used to attach the optical connector to a backplane, the clip removing tool being characterized by comprising a removing tool main body advanced toward or retreated from the optical connector and disengaging pieces projecting from the removing tool main body, and in that the disengaging pieces are pushed against engaging pawls projecting from side portions of elastic pawl leading end portions of the clip, to deform the engaging pawls to reduce the amount of parts of the engaging pawls which project from the elastic pawl leading end portions, thus disengaging the engaging pawls from the optical connector.
In this case, the disengaging pieces are pushed against, for example, the engaging pawls projecting from the side portions of the elastic pawl leading end portions of the clip to deform the engaging pawls, thus reducing the amount of parts of the engaging pawls which project from the elastic pawl leading end portions.
Furthermore, the disengaging pieces of the clip removing tool may be rotatably supported on the removing tool main body, and may each comprise, at its leading end in a direction in which the disengaging piece projects from the removing tool main body, an engaging pawl pushing portion that pushes the corresponding engaging pawl to reduce the amount of part of the engaging pawl which projects from the elastic pawl leading end portion, thus disengaging the engaging pawl from a locking portion provided in the optical connector, and an abutting portion that pushes the corresponding elastic pawl as the removing tool main body advances toward the optical connector.
Alternatively, the removing tool main body may be provided with an attachment used to separately attach an operation handle for an operation of advancement toward or retreat from the optical connector.
Furthermore, the removing tool main body may be provided with a holding engaging portion that engages with the optical connector.
A second aspect of the present invention is a clip removing method of disengaging an optical connector from a clip used to attach the optical connector to a backplane, the method being characterized by comprising pushing a holding tool against the backplane to disengage the clip from the optical connector.
In this case, elastic pawls are disengaged from the optical connector by, for example, disengaging the elastic pawls of the clip from the optical connector held using the holding tool and then removing the optical connector from a neighborhood of the backplane together with the holding tool. More specifically, for example, engaging pawls projecting from side portions of elastic pawl leading end portions of the clip are pushed to reduce the amount of parts of the engaging pawls which project from the elastic pawl leading end portions. Then, with this state maintained, the elastic pawl leading end portions are pushed to move the elastic pawls to positions where the engaging pawls do not engage with the optical connector.
In the first and second aspects of the present invention, the xe2x80x9coptical connectorxe2x80x9d attached to the backplane may have any configuration and may be, for example, the backplane housing of the backplane connector.
Furthermore, the holding tool used in the second aspect of the present invention may be the above described clip removing tool comprising a holding engaging portion or an exclusive holding tool which is separate from the clip removing tool and which is used to hold the optical connector by engagement, fitting, gripping, or the like. However, a holding tool also used as a clip removing tool is more advantageous in that it enables the elastic pawls of the clip to be disengaged from the optical connector while simultaneously holding the optical connector, in that it allows the optical connector to be removed easily (operability), in that it serves to reduce costs, and the like.